With the increased availability of broadband Internet connections, the use of Voice over Internet Protocol (VoIP) to make telephone calls over the Internet has also increased. In many cases, telecommunications service providers (SPs) implement voice communications systems that provide various services to subscribers, such as interactive voice response (IVR) applications. In IVR applications, an individual on one end of the call interacts with an IVR system on the other end of the call. The IVR system may be implemented in a device such as a Session Border Controller (SBC), TDM-IP gateway etc. Typically, the IVR system plays pre-recorded voice prompts in response to which the individual speaks a response or presses a number on the telephone keypad to select an option. One common application for IVR systems is a calling card service in which a subscriber places an initial call to an SBC, which provides a voice menu to prompt the subscriber to provide identification and target destination information. The information may be entered by the subscriber by pressing keys on the telephone keypad, which generates dual-tone multi-frequency (DTMF) signals corresponding to the pressed keys.
The extension of the call from the SBC to the target endpoint may be performed in a variety of ways. In flow-through systems, the media traffic between the originating and terminating endpoints flows through the SBC. Thus, the SBC can monitor the communications between the endpoints. In flow-around systems, the media traffic flows directly between the endpoints without passing through the SBC. In flow-through systems, the SBC must process each incoming packet, so the load on the SBC can be significant. As a result, the total number of simultaneous calls that may be supported may be decreased, and a media switching delay may be introduced. Flow-around systems may eliminate some of these problems by bypassing the SBC for media communications. However, in flow-around systems, the SBC can no longer monitor the audio and other media communications from the originating endpoint, thereby cutting off media communication from the originating endpoint and the SBC. In some flow-through systems, the communications between the endpoints is encrypted using, e.g., Secured Real-time Transfer Protocol (SRTP). Thus, even if the media flows through the SBC, the SBC is unable to monitor the communications from the originating endpoint. This restraint on the endpoint's ability to communicate with the SBC can limit the types of services provided by the SBC after the original connection to the terminating endpoint is established.
Accordingly, it would be desirable to provide systems and methods for voice communication that enable the voice communications systems to more effectively communicate with the call endpoints.